Many people donât realize that chest pain and shortness of breath can be symptoms of RA. In fact, heart and lung problems can be a serious complication of the disease. People with RA have an increased incidence of blocked and hardened arteries, which could lead to heart attack or stroke, especially if they also smoke.
Calcium carbonate spicules of calcareous sponges have been found in Early Cambrian rocks from about 530 to 523 million years ago in Australia. Other probable demosponges have been found in the Early Cambrian Chengjiang fauna, from 525 to 520 million years ago. Freshwater sponges appear to be much younger, as the earliest known fossils date from the Mid-Eocene period about 48 to 40 million years ago.
Nevertheless, sponges are in fact the oldest living animals, one of the most amazing success stories on the planet. Argument rages over exactly how old the earliest sponge is. Some fossils that are claimed to be sponges have been dated back to around 710 MY ago, but not everyone accepts these.ut that doesnât make sponges âprimitiveâ, or in any way lesser beings. They have been on our planet for longer than any other animal â around 10,000 times longer than our species. They have survived repeated mass extinction events, and that suggests they will probably be around for at least another 600 MY.